OPTIMIZATION OF ULTRASOUND-ASSISTED EXTRACTION OF OLIVE LEAF (var. HALHALI) EXTRACTS

Abstract

In this study, the effects of three different independent variables (extraction temperature, extraction time, ultrasonic power) on the total phenolic content, extraction yield and antioxidant capacity (IC50) value of olive leaf extracts of Halhalı variety which is originated from South-eastern Anatolia Region were investigated. As a result of the evaluation made with Box-Behnken Design Model, the optimum conditions were determined as 62.94°C, 50.67 min, and 64.65% ultrasonic power for the optimization of ultrasonic-assisted extraction. In order to visualize the effect of extraction method on TPC, extraction yield and IC50 value of olive leaf extracts, results of three extraction methods were compared. The differences among the mean values of the investigated parameters in terms of extraction method were found significantly different (P<0.05). In addition, it can be inferenced that ultrasound assisted extraction accelerated the transition of phenolic substances to solvent in terms of SEM images and investigated other parameters.

Bioactivity, DNA damage protecting, and aroma potential of oleuropein enriched olive leaf extract by optimization of ultrasound‐assisted process

“…TPC in UAE was ranged from 6.78 ± 0.068 to 41.62 ± 0.069 mg GAE/g dry leaves (Elhussein & Şahin, 2018). In another study examining the effects of temperature, time, and ultrasonic power on TPC for optimizing the UAE of olive leaf; TPC was found to be among 20.57–53.89 mg‐GAE/g dry leaves (Ünver, 2018). The effects of different solvents on TPC of olive leaf were determined and TPC of the samples which were left to extraction for 24 h ranged from 16.52 to 24.93 mg GAE/G dry matter (Abaza et al, 2011).…”